Milk proteins production process

Milk protein products. As indicated in Table 1, the food industry is placing major emphasis on the production and utilization of milk protein products in a wide variety of formulated food products (20,21,22). Although nonfat dry milk (NFDM) and whey powder are major milk protein ingredients in formulated foods, casein and whey protein concentrates, which contain their proteins in a more highly concentrated and functional form, are essential for certain food product applications, such as those products that require the proteins as an emulsifier agent. Additional details on the processing methods and conditions used to produce the various milk protein products are available (23). 

Whey protein concentrates (WPC), which are relatively new forms of milk protein products available for emulsification uses, have also been studied (4,28,29). WPC products prepared by gel filtration, ultrafiltration, metaphosphate precipitation and carboxymethyl cellulose precipitation all exhibited inferior emulsification properties compared to caseinate, both in model systems and in a simulated whipped topping formulation (2. However, additional work is proceeding on this topic and it is expected that WPC will be found to be capable of providing reasonable functionality in the emulsification area, especially if proper processing conditions are followed to minimize protein denaturation during their production. Such adverse effects on the functionality of WPC are undoubtedly due to their Irreversible interaction during heating processes which impair their ability to dissociate and unfold at the emulsion interface in order to function as an emulsifier (22). 

Membrane processing. The use of ultrafiltration (UF) for the production of whey protein concentrates (WPCs) is now well established (p. 223). Obviously, UF or diafiltration (DF) can be used to prepare products enriched in total milk protein. Products with protein concentrations up to 85% have been produced and assessed for a range of functionalities and applications (Fox and Mulvihill, 1992). 

The following factors appear to control the emulsification properties of milk proteins in food product applications 1) the physico-chemical state of the proteins as influenced by pH, Ca and other polyvalent ions, denaturation, aggregation, enzyme modification, and conditions used to produce the emulsion 2) composition and processing conditions with respect to lipid-protein ratio, chemical emulsifiers, physical state of the fat phase, ionic activities, pH, and viscosity of the dispersion phase surrounding the fat globules and 3) the sequence and process for incorporating the respective components of the emulsion and for forming the emulsion. 

The mix is then homogenized at 105 to 210 kg/cm2 (1500 to 3000 lb/in2) to subdivide milk fat globules to sizes ranging from 0.5 to 2 m in diameter. This process is essential to produce a mix with adequate aeration properties so that the final product will contain < 175- m-diameter air cells to contribute a smooth texture. The homogenized mix is cooled and aged to fully hydrate the hydrocolloids, e.g., milk proteins, stabilizers and corn sweetners, and to provide adequate viscosity to the mix. 

MILK AND MILK PRODUCTS. Intricate chemical and microbiological problems arise in the production, processing, and distribution of milk products. Milk is a complex mixlure of fat (40 ). protein (3.5 3 I. carbohydrate (4.8rf) and mineral components t().7 ) and is an excellent hacleria growth medium hence the need for care and cleanliness in handling. 

Milk proteins are subdivided into random coiled caseins, which can be precipitated by acidification of raw skim milk to pH 4.6 at 20°C, and into more globular whey proteins, which remain in the serum after precipitation of the caseins (42). In Table 8, an overview is given of the molecular structure and basic properties of the major protein fractions present in milk. Some specific properties that might be of importance for their determination in foods and food products are also listed. For the young of mammals, including humans, milk is the first and, for most, the only food ingested for a considerable period of time. With the domestication of animals, it became possible to include milk in the diet of adult humans as well. For much of the world, particularly in the West, milk from cattle (Bos taurus) accounts for nearly all the milk processed for human consumption (43). 

Table I shows the furosine content of the milk-crumb and soya-crumb samples in comparison to other food protein sources thermally processed. Milk—crumb has the highest furosine content, probably due to the free lysine and glucose added in the production moreover, the milk protein has also a considerable level of protein-bound lysine.

The objective of the two membrane processes shown in Figure 6.22 is to increase the fraction of milk proteins used as cheese or some other useful product and to reduce the waste disposal problem represented by the whey. In the MMV... 

Unstabilized bran and polish have been used almost exclusively for animal feed, due to the bitter flavor that develops from the lipolytic action of enzymes on the oil found in them. However, development of a thermal process that inactivates the lipases has resulted in a stabilized rice bran product that is suitable for the food industry. The impressive nutritional qualities of the oil, fiber, carbohydrate and proteins of rice bran have made it a valuable food material. Removal of fiber from the bran by physical K,J7or enzymic1819 processes produces a milk-like product having desirable nutritional and functional properties. The nutritional composition of the rice bran milk product described by California Natural Products has been shown to match the nutritional requirements of an infant formula. Originally, the anti-nutritional factor of the residual phytates was of concern. However, as of 2005, phytase enzymes are suitable for use to break down these phytates. 

The actual and potential use of milk proteins as food ingredients has been a popular topic for research over the past 30 years. Milk and dairy products have numerous advantages over competitors when used as ingredients they are colorless, have a bland taste, are rather stable to processing, are free of... 

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